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Inner-shell single and double ionization potentials of aminophenol isomers
Nikolai V Kryzhevoi1, Robin Santra, Lorenz S Cederbaum
1Theoretical Chemistry, Institute of Physical Chemistry, Heidelberg University, 69120 Heidelberg, Germany. nikolai.kryzhevoi@pci.uni-heidelberg.de
The Journal of Chemical Physics
|September 8, 2011
Summary
This study investigates core ionization potentials of aminophenol isomers. Double ionization potentials reveal structural differences, enabling isomer characterization using x-ray two-photon photoelectron spectroscopy.
Area of Science:
- Physical Chemistry
- Quantum Chemistry
- Spectroscopy
Background:
- Aminophenol isomers (para-, meta-, ortho-) exhibit distinct electronic structures.
- Understanding core ionization potentials is crucial for molecular characterization.
- X-ray photoelectron spectroscopy (XPS) is a common tool for electronic structure analysis.
Purpose of the Study:
- To comprehensively study single and double core ionization potentials of aminophenol isomers.
- To clarify the influence of relaxation, correlation, relativistic, and basis set effects.
- To explore the isomer-specific nature of these ionization potentials.
Main Methods:
- Theoretical calculation of single and double core ionization potentials.
- Comparison with phenol and aniline molecules.
- Analysis of relaxation, correlation, and relativistic effects.
Main Results:
- Single core ionization potentials show minimal variation across aminophenol isomers, challenging XPS differentiation.
- Double core ionization potentials exhibit significant isomer dependence due to structural arrangements and relaxation effects.
- Electrostatic repulsion and relaxation effects are critical in double ionization.
Conclusions:
- Double core ionization potentials offer a sensitive probe for distinguishing aminophenol isomers.
- X-ray two-photon photoelectron spectroscopy (XTPES) can effectively characterize aminophenol electronic structures.
- Isomer-specific electronic properties are discernible through advanced spectroscopic techniques.
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